New York News
In the HighlY Interactive ParticlE Relics (HYPER) model, some time after the formation of dark matter in the early Universe, the strength of its interaction with normal matter increases abruptly — which on the one hand, makes it potentially detectable today and at the same time can explain the abundance of dark matter.
Phase transition in the early Universe changes strength of interaction between dark and normal matter. Image credit: University of Adelaide.
Dark matter is the mysterious substance that makes up roughly a quarter of the Universe.
There is strong indirect evidence for its existence from measurements of cosmic primordial radiation, anomalies in the radial dependence of galactic rotational curves and gravitational lensing.
Despite its apparently pivotal role in the Universe the physical origin of dark matter remains unknown.
Theoretical physicists suspect that it is made of unseen particles that neither reflect nor absorb light, but are able to exert gravity.
Since the search for one of leading candidates, called weakly interacting massive particles (WIMPs), has not yet led to success, the research community is looking for alternative candidates, especially lighter ones.
At the same time, one generically expects phase transitions in the dark sector — after all, there are several in the visible sector. But previous studies have tended to n